Ice sliding on nanoscale-smooth surfaces and the role of the quasi-liquid layer

Understanding ice adhesion and detachment from solid surfaces is essential for the rational design of effective icephobic coatings. In this study, we present a peculiar regime of ice sliding on surfaces with a roughness in the nanometer range, demonstrating that sliding can be consistently observed on various surfaces, including glass and polysaccharide-based monolayer coatings. Such sliding can be interpreted as the macroscopic manifestation of an interfacial layer, often referred to as quasi-liquid layer or pre-molten layer. To test the hypothesis, ice sliding experiments were conducted at different pushing speeds, roughness values and temperatures, on bare and coated glass, providing information on the nanoscale surface properties and behavior of ice at the interface. As such, we pave the way to the rational design of nanoscale-smooth surfaces and materials, that take advantage of interfacial quasi-liquid layer to reduce ice adhesion. Also, polysaccharides are non-toxic and biodegradable, properties that make them suitable as sustainable environmental-friendly coatings.